These are diagrams, animations, movies, and time-lapse recordings that I’ve made. Feel free to use them for personal, teaching, or presentation purposes. For an item that has has already been published, please cite the paper that is listed with it. For unpublished materials, please cite this website as the source. If you’d like to adapt any of these materials for use in a publication, please contact me directly (donoughe [at] fas.harvard.edu).
- Time lapses of cricket embryogenesis
- Animations of generalized early development
- Overview of cricket development
- Cricket reference poster
Time-lapses of cricket embryogenesis
The above GIF shows katatrepsis, the period of development when many insects do a backwards somersault in the egg. The GIF is an exerpt from the following timelapse of the first eight days of cricket development:
This is a ventrolateral view of a cricket embryo during the first eight days of development, taken at an ambient temperature of 25 degrees C using bright field microscopy. Images were taken every 5 minutes. For the first half of the movie, an embryo was submerged in Halocarbon Oil 700. From day 3 onwards, the embryo was submerged in water to allow visualization of the normal expansion of the egg via water uptake that happens at this time. Hatching usually occurs four to six days after the last time point shown here, which is equivalent to 10-12 days after egg laying at 29 degrees C.
A longer version of this time lapse with detailed annotations has been published as two separate supplemental movies in Donoughe and Extavour (Developmental Biology 2016). These are screenshots of the movies:
If you are interested, the annotated movies can be downloaded from the article’s page on the Developmental Biology website.
Animations of generalized early development
I made these animations for teaching purposes. The first illustrates holoblastic cell cleavage, which means that nuclei divide in tandem with complete cell divisions. In particular, this animation shows a radial cleavage pattern, an orientation of divisions that is observed in sea urchins, for instance.
The second animation shows an embryo with superficial cleavage. The nuclei divide without any accompanying cell division. This is the mode of early development for most insects.
These divisions – also called syncytial divisions – are later followed by meroblastic cell cleavage, which means that the cleavage plane does not extend into the yolk.
To make these animations, I drew the frames on paper, scanned them, and assembled the frames in Photoshop.
overview of cricket development
This is a modified version of Figure 1 in Donoughe and Extavour (Developmental Biology 2016).
Cricket reference poster
This poster is an amalgamation of nearly everything I know about the embryogenesis of Gryllus bimaculatus. It includes most of the figures from Donoughe and Extavour (Developmental Biology 2016), a figure from Nakamura et al (Current Biology 2010), and several from Kainz (PhD Thesis 2009). It also includes summaries of additional staging information from five other publications.
Printed at full size, this poster is 130cm x 60cm (51″ x 24″). Contact me if you would like the high resolution PDF; I’d be happy to share it.